Sealing structure of plunger pump

ABSTRACT

A sealing structure of a plunger pump, comprising: a pump body and a plunger rod assembly disposed in the pump body; wherein the pump body includes an upper pump and a lower pump, and the upper pump and lower pump are fixed by screw connection; a sealing ring provided between the upper pump and the lower pump; wherein the plunger rod assembly includes an annular groove disposed at a position adjacent to a lower portion of the plunger rod at an outer peripheral surface thereof; a dynamic lip seal fitted in the annular groove; and a static lip seal sleeved on the outer peripheral surface of the plunger rod; the sealing structure of the plunger pump has good sealing effect, good anti-wear and anti-wear effect, simple replacement and low maintenance cost.

BACKGROUND OF THE INVENTION (1) Field of the Juveniles

The present invention relates to a sealing structure of plunger pump.

(2) Description of the Related Art

A plunger pump, which relies on the plunger in the cylinder to doreciprocating motion, allows the seal to move the volume of the chamberto the suction and pressure fluid, which is widely used in highpressure, large flow, and flow needs to be adjusted.

The plunger pump usually includes a pump body, plunger rod and plunger,the sealing structure in the pump body is too simple, so in theultra-high pressure state, the reciprocating frequency of the plungerrod is higher, the heat generated between the sealing structure and theplunger rod will seriously affect the sealing performance and reduce theservice life. Moreover, the sealing structure is a wearing part, theservice life has a certain limit, so the sealing structure needs to bereplaced frequently, and the existing pump body is usually an integralstructure, which causes inconvenience to use.

SUMMARY OF THE INVENTION

The technical problem to be solved by the present invention is toprovide a sealing structure of a plunger pump which is resistant tocorrosion, wear resistance, long service life and easy replacement.

In order to solve the above technical problems, the technical solutionof the sealing structure of the plunger pump of the present inventionis:

A sealing structure of a plunger pump, comprising: a pump body and aplunger rod assembly disposed in the pump body; wherein the pump bodyincludes an upper pump and a lower pump, and the upper pump and lowerpump are fixed by screw connection; a sealing ring provided between theupper pump and the lower pump; a feed inlet disposed on the lower pumpand a discharge outlet disposed on the upper pump; a lock nut disposedat an upper end of the upper pump; wherein the plunger rod assemblyincludes a plunger rod which extends into the pump body through athrough hole in the center of the lock nut; a dust boot disposed betweenthe plunger rod and the through hole; an annular groove disposed at aposition adjacent to a lower portion of the plunger rod at an outerperipheral surface thereof; a dynamic lip seal fitted in the annulargroove; and a static lip seal sleeved on the outer peripheral surface ofthe plunger rod; wherein the static lip seal having an upper end isdisposed on a first seal ring and having a lower end is disposed on afirst positioning seat; the first positioning seat is disposed on a stepof an inner wall of the pump body and the first seal ring is disposed ona bottom surface of the lock nut.

More preferably, wherein the static lip seal and an inner wall of theupper pump have at least two gasket rings disposed therebetween.

More preferably, wherein the dynamic lip seal includes a second sealring disposed at a top surface thereof and a second positioning seatdisposed at a bottom surface thereof; the second seal ring and thesecond positioning seat are fitted in the annular groove, and areabutted against top and bottom surfaces of the annular groove,respectively.

More preferably, wherein the feed inlet of the lower pump includes afeeding seal ring disposed thereon; a feed valve seat disposed at thelower pump adjacent to a bottom, surface of the feed inlet; a limitingseat attached to the feed valve seat; a lower pump sealing ring disposedbetween the feed valve seat and a bottom surface of the lower pump; anda valve ball disposed in an accommodating space which is formed betweenthe limiting seat and the feed valve seat.

The technical effect achieved by the present invention is:

Compared with the prior art, the plunger pump has a sealing structure inthe upper and lower parts of the plunger rod, and the sealing structureis a lip structure, which is resistant to wear and corrosion, and has along service life.

Compared with the prior art, the sealing structure of the plunger pumpof the present invention is that the pump body is divided into an upperpump and a lower pump, and the sealing structure is easy to be replaced,and the maintenance cost is reduced.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic view of a sealing structure of plunger pump of thepresent invention.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIG. 1, the present invention provides a sealing structureof a plunger pump, comprising a pump body 1 and a plunger rod assembly 2disposed in the pump body 1. The pump body 1 includes an upper pump 3and a lower pump 4, and the upper pump 3 and lower pump 4 are fixed byscrew connection; a sealing ring 5 provided between the upper pump 3 andthe lower pump 4; a feed inlet 6 disposed on the lower pump 4 and adischarge outlet disposed on the upper pump 3; a discharge connector 7disposed on the discharge outlet; a lock nut 8 disposed at an upper endof the upper pump 3. The plunger rod assembly 2 includes a plunger rod 9which extends into the pump body 1 through a through hole in the centerof the lock nut 8; a dust boot 10 disposed between the plunger rod 9 andthe through hole; an annular groove 11 disposed at a position adjacentto a lower portion of the plunger rod 9 at an outer peripheral surfacethereof; a dynamic lip seal 12 fitted in the annular groove 11; and astatic lip seal 13 sleeved on the outer peripheral surface of theplunger rod 9. The static lip seal 13 having an upper end is disposed ona first seal ring 14 and having a lower end is disposed on a firstpositioning seat 15. The first positioning seat 15 is disposed on a stepof an inner wall of the pump body 1 and the first seal ring 14 isdisposed on a bottom surface of the lock nut 8.

The static lip seal 13 and an inner wall of the upper pump 3 have atleast two gasket rings 17 disposed therebetween.

The dynamic lip seal 12 includes a second seal ring 18 disposed at a topsurface thereof and a second positioning seat 19 disposed at a bottomsurface thereof; the second seal ring 18 and the second positioning seat19 are fitted in the annular groove 11 and abutted against top andbottom surfaces of the annular groove 11, respectively.

The feed inlet 6 of the lower pump 4 includes a feeding seal ring 20disposed thereon; a feed valve seat 21 disposed at the lower pump 4adjacent to a bottom surface of the feed inlet 6; a limiting seat 22attached to the feed valve seat 21; a lower pump sealing ring 23disposed between the feed valve seat 21 and a bottom surface of thelower pump 4; and a valve ball 24 disposed in an accommodating spacewhich is formed between the limiting seat 22 and the feed valve seat 21.

The following describes the working principle of the present invention:

The plunger pump of the present invention, a pumped object is passedthrough the feed inlet 6 of the lower pump body 4 and into a lower space26 bounded by a piston 25 of the pump body 1 via the valve ball 24, andenters an upper space 27 bounded by the piston 25 from a passage at thebottom of the plunger rod 9, and is finally discharged from thedischarged outlet disposed above the upper space 27 of the pump body 1.

The above-mentioned process is carried out by reciprocating motion ofthe plunger rod 9 to drive the piston 25. During the high-speedreciprocating motion, the dynamic lip seal 12 moves up and down with theplunger rod 9 and is always tightly fitted between the plunger rod 9 andthe inner wall of the pump body 1, thereby improving the stability ofthe plunger pump; the static lip seal 13 is provided between the plungerrod 9 and the inner wall of the pump body 1, and the dynamic lip seal 12is applied so that the sealing effect of the plunger pump is better, andthe structure of the dynamic lip seal 12 and the static lip seal 13allows the plunger pump have a long service life and good anti-weareffect. In addition, it is only necessary to open the upper pump 3 andthe lower pump 4 when replacing the dynamic and static lip seal 11, 12,so it is more convenient to replace the parts.

The above only describes some exemplary embodiments of the presentinvention. Those having ordinary skills in the art may also make manymodifications and improvements without departing from the conception ofthe invention, which shall all fall within the protection scope of theinvention.

1. A sealing structure of a plunger pump, comprising: a pump body and aplunger rod assembly disposed in the pump body; wherein the pump bodyincludes an upper pump and a lower pump, and the upper pump and lowerpump are fixed by screw connection; a sealing ring provided between theupper pump and the lower pump; a feed inlet disposed on the lower pumpand a discharge outlet disposed on the upper pump; a lock nut disposedat an upper end of the upper pump; wherein the plunger rod assemblyincludes a plunger rod which extends into the pump body through athrough hole in the center of the lock nut; a dust boot disposed betweenthe plunger rod and the through hole; an annular groove disposed at aposition adjacent to a lower portion of the plunger rod at an outerperipheral surface thereof; a dynamic lip seal fitted in the annulargroove; and a static lip seal sleeved on the outer peripheral surface ofthe plunger rod; wherein the static lip seal having an upper end isdisposed on a first seal ring and having a lower end is disposed on afirst positioning seat; the first positioning seat is disposed on a stepof an inner wall of the pump body and the first seal ring is disposed ona bottom surface of the lock nut; wherein the static lip seal and aninner wall of the upper pump have at least two gasket rings disposedtherebetween; wherein the dynamic lip seal includes a second seal ringdisposed at a top surface thereof and a second positioning seat disposedat a bottom surface thereof; the second seal ring and the secondpositioning seat are fitted in the annular groove, and are abuttedagainst top and bottom surfaces of the annular groove, respectively;wherein the feed inlet of the lower pump includes a feeding seal ringdisposed thereon; a feed valve seat disposed at the lower pump adjacentto a bottom surface of the feed inlet; a limiting seat attached to thefeed valve seat; a lower pump sealing ring disposed between the feedvalve seat and a bottom surface of the lower pump; and a valve balldisposed in an accommodating space which is formed between the limitingseat and the feed valve seat.